


Turn the Earth Backwards

by mallardeer



Category: Supergirl (TV 2015)
Genre: F/F
Language: English
Status: In-Progress
Published: 2020-03-17
Updated: 2020-03-17
Packaged: 2021-03-01 00:15:37
Rating: General Audiences
Warnings: Major Character Death
Chapters: 1
Words: 4,543
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/23186119
Author URL: https://archiveofourown.org/users/mallardeer/pseuds/mallardeer
Summary: “There’s a girl,” she finally admits, “in Lena’s office who looks just like her. Like…she has to be either herself from the past or her daughter from the future is how much she looks like Lena. And she looked at me…like she hated me.”
Relationships: Kara Danvers/Lena Luthor
Comments: 8
Kudos: 156





	Turn the Earth Backwards

**Author's Note:**

> Listen, in these trying times, I figured I should share my attempt at a popular trope: daughter from the future!!! If you read my Domestic Life series (and who HASN'T??), you'll recognize the kids in this one. Anyway, take a break from reality for a minute if you feel so inclined. That's why we're all here, eh?

“What do you mean you couldn’t save her? What is the POINT of being Supergirl if you couldn’t save her?” 

“Ash!” Ronan scolds reflexively, but Kara sees the exact same question in his eyes. 

“I don’t know, Aislin,” Kara says, utterly defeated. “I don’t know.”

The only thing her daughter has for her is scorn, so she makes no move to stop her as she grabs up a jacket and explodes out of the house. Her son remains, silent and unmoving, and with eyes the exact same shade as his mother’s. She cannot meet those eyes. “Mom,” he says softly, “she’ll be okay.”

Ronan, like Lena, has only ever worried about whether everyone else is all right. She cannot take the solicitousness from him, this gangly fifteen-year-old boy with green eyes and a soft, trusting smile. Kara shakes her head. “If she is, she’s stronger than me.” 

As soon as she’s said that out loud, she regrets it. Ronan is a child—her child—and she should not be putting her brokenness on him to deal with. 

“Mom,” he says, choking on a sob, so she does the only thing she can do: gathers him up into her arms and kisses his forehead. 

“I’m here, Ro,” she promises. 

He fights it for a moment, but then he breaks down and starts howling. The noise is quite possibly the worst thing Kara has ever heard, but she holds him tight. “I’m sorry,” he mumbles, some minutes later, but Kara just dries his tears and kisses him. 

“Never apologize for that, Ronan,” she says softly. 

“Do you want me to go get Ash?” he asks, and she reluctantly shakes her head. 

“Let’s let her have some time by herself.” 

“What do we do now?” 

Kara’s heart collapses in on itself. She has no idea. 

\--

One of Clark’s favorite conspiracy theories about Superman is that there was one time when Lois Lane died, and Superman flew around the earth, against its revolution, so fast it actually reversed time. So he was able to save her, in the end. 

She knows that’s not how time—or the earth—works. 

What she wouldn’t give for that to be how time works. “You wanna try it?” her cousin offers with a gentle smile, making a “round the world” motion with his finger. “You were always faster than me—maybe that’s what it needs.”

“Kal,” she sighs, but smiles a watery smile, and accepts his affectionate hug. She wonders briefly if Alex called him, but it doesn’t matter. He’s here when she needs him. 

“I’m so sorry, Kara,” he murmurs, and she kisses him. “How are the kids?”

She sighs heavily, and he holds her tight against his side. “Ronan sobbed himself to sleep on the couch. Aislin is hiding from me.”

“She blames you.”

“What’s the point of being Supergirl if you can’t save the people you love?”

Clark nods solemnly. “I probably would have tried it, flying around the earth, if it were Lois.”

Kara snorts. “That’s because you had a terrible earthling education.”

He laughs and kisses her head. “And because you’ve always been stronger than me.”

“I came so close to…blowing up the whole entire block. If Alex and J’onn hadn’t gotten there in time, I probably would have.”

She knows he must think he knows exactly how she feels. She doesn’t even want to think about what he’d do if something happened to Lois or Jonathan. 

But he’s never had to lose anyone. Not like she has. Once that would have made her bitter; now she’s actually glad that he has no idea what this feels like. To love and love and love—and have that love extinguished over and over. Her parents, her family, her planet, her home. Lena.

Another sob bubbles up, and Clark holds her, and she just lets him enfold her in his arms. 

\--

He stays and makes sure she and Ronan eat. When she leaves to go get Aislin, he promises he’ll stay until they come back. She kisses both of them and heads out. She’s known the whole time where Aislin is, as she’s never been able to stop listening for the sound of her heartbeat. She can’t identify everyone’s heartbeats—normal human heartbeats are virtually identical—but Lena’s and her children’s are seared into her brain. 

She hadn’t realized that Lena had given their daughter a security badge to get into the labs, but that’s where Aislin’s heart is tapping out its rhythm, and so she makes her way there, until suddenly there’s a silence. On the verge of panic, she scans around for that noise that’s never left her since before Aislin was born, even, and she can’t find it. 

Her daughter is gone.

\--

“Ms. Luthor, there is a very anxious young woman barricaded in your office,” Jess greets her nervously, as they walk back from lunch, and Kara instantly gets her hackles up.   
“Thank you, Jess,” Lena says calmly. “Kara,” she warns gently, and Kara takes a breath. 

“She can’t be more than twelve,” Jess offers helpfully. “I didn’t…want to call security.”

“I completely understand,” Lena assures her, and Kara decides to head into Lena’s office herself. 

“Hello,” she says cheerfully to the girl, who’s crouched low beside Lena’s desk. “My name’s—”

“I know who you are,” the girl spits, and Kara is taken aback by the venom in her voice. “Where’s Lena Luthor?”

“I’m right here,” Lena says smoothly. “What can I do for you?”

The girl looks up at Lena, and all the color drains from her face. “It’s you—you’re…” Tears start pouring down her face, and then she’s up on her feet and launching herself at Lena. Bemused, Lena catches the girl and smooths her hair. Kara stands in the doorway, bewildered. The girl… She has Lena’s green eyes exactly. The way she’d said, “I know who you are,” was with Lena’s own voice. 

Who is she?

“Sweetheart, what is it?” Lena asks softly, and the girl only cries harder. 

\--

The worst part, she thinks, is that there’s no trace of Aislin in the whole building. The whole city. The whole planet. Winn tries to tell her that means she can’t possibly be dead, but what difference does it make? 

She’s gone. 

She cannot bear to go home to tell Ronan and Clark. 

\--

“What’s your name?” Kara asks, but the girl only clings to Lena. “Okay, I think I’m not helping. Call you later?” 

Lena nods, and Kara quietly slips away. Left alone with a sobbing twelve-year-old, Lena can only do what she wishes someone would have done for her when she was that age. She gently carries the girl to the couch and holds her until she cries herself to sleep. After several minutes, she carefully settles her on a pillow and goes to speak with Jess about where the girl came from. 

“I don’t know. I don’t know how she got past security. I looked up, and she was in your office. I’m very sorry, Ms. Luthor.”

“It’s all right, Jess,” Lena says absently. “Can you please send for today’s security footage? All available cameras?”

“Of course.”

She returns to her office and locks the door, deciding to keep her mysterious foundling with her until she can get to the bottom of this. 

\--

Kara goes back to Catco, but cannot concentrate on anything, so she ends up at the DEO to badger Winn about time travel. He says it’s theoretically possible, and she should know that—she does—but no one has ever been able to create a machine that can control how things move through time. As far as he knows. 

“There’s a girl,” she finally admits, “in Lena’s office who looks just like her. Like…she has to be either herself from the past or her daughter from the future is how much she looks like Lena. And she looked at me…like she hated me.”

Winn blinks, clearly unsure what to do with this information. “Well, if it’s Lena...from the past, she can’t…know who you are yet, right? So then…”

“It’s her daughter from the future,” Kara decides, and Winn laughs a little, before realizing she’s not joking.

“Kara…”

“Well! What else could it be?”

“A coincidence? Lena Luthor is not the only person with dark hair and green eyes on the planet.”

Kara huffs and begins pacing. “Fine, fine. I guess… I guess Lena can handle this, whatever it is.”

\--

The security footage is baffling. The girl appeared in a locked basement of the tower and used what appears to be an authentic security badge to get to her office, darting in when Jess got up to retrieve something from the printer. There was no angle that showed how she’d gotten into the basement. 

Carefully, Lena approaches the sleeping girl and tries to check her pockets, but she jolts awake as soon as Lena touches her. “Mom?” she yawns sleepily, and Lena starts back, shocked. 

“I’m sorry, sweetheart,” she says softly, and the girl wakes up and blushes. 

“Oh. I forgot. Um.” She’s clearly at a loss. “I was just… Um, I was supposed to find Lena Luthor, and you’re her, and now I don’t know…” She shrugs and stares at her sneakers. 

“It’s okay. We’ll figure out what to do, together,” Lena assures her. “But first, how about you tell me your name?”

“Oh, it’s… Aislin,” she says quietly.“All right, Aislin, are you hungry? I’m supposed to have dinner with Kara, but—”

“Don’t,” Aislin begs, and Lena frowns. “Don’t go near Kara Danvers. She’s dangerous.”

Lena’s only known for a few weeks that her best friend is Supergirl, but she still can’t bring herself to consider that Kara is dangerous. “What do you mean?” 

“I mean, she’s… Well, she can’t…” Frustrated, the girl bursts into tears again. 

Lena bites on a sigh. She’s never, ever considered herself maternal, so she has no idea what to do here, but this lost, forlorn child is beginning to remind her uncomfortably of herself. “Don’t cry, Aislin. Let’s just get you somewhere safe, okay?”

\--

“Lena!” Kara is beyond relieved when her phone rings. “What’s going on?”

“I took her home. She told me her name, but she won’t tell me anything else. Oh, except that you’re dangerous.”

“Okay, she’s not wrong,” Kara says, and Lena snorts derisively. 

“Kara, what do I do with her?”

Kara sighs and debates telling Lena her theory. “Feed her,” she decides to say. “Everything looks better to a kid when they’re not hungry.”

Lena laughs. “I’m sorry about this. I was looking forward to tonight.”

“Me too,” Kara says softly. “But I can be patient.”

“Thank you,” Lena says.

\--

Lena doesn’t really know what kids like, so she just orders Kara’s favorite foods, figuring at least some of them will appeal to a child’s palate. And, just like Kara, an eager Aislin piles her plate high with pizza and Chinese dumplings. Lena sits and watches, amused, as Aislin’s mood completely changes now that she’s eating. Her eyes light up in a way that reminds her forcefully of Kara, and she has to look away. 

“Where are your parents, sweetheart?” she asks, when Aislin finally takes a breath. 

“My mom’s dead. My other mom’s probably home or something with my brother,” she replies, unconcerned. 

“I’m sorry,” Lena says, heart twinging. “Do you think your mom and your brother are worried about where you are?”

“No. They don’t care about me, just each other. But that’s okay, because I’m here now.”

“They don’t care about me, just each other” is a bolt right through Lena’s heart. Now the only thing she can think of is protecting this girl from the kind of heartbreak she experienced in her childhood. 

But… does she have time to take care of a kid? Can she just take a kid from its parent?

Of course she can’t. She’ll keep Aislin tonight, and then she’ll call the police or whatever proper authorities will get her united with her family. 

She cleans up after dinner and lets Aislin fall asleep in her lap as they watch TV. Eventually, she gets up and carries the girl to her bed, carefully smoothing the blankets over her. 

She’ll get her reunited with her family, but there’s no reason she can’t check in on her afterward. 

\--

In the morning, however, Aislin is adamantly against going back to her family. “They’re not here anyway,” she says, and Lena frowns. 

“What do you mean? Where are they?”

“Well, I guess… They are…here,” she says thoughtfully. “Anyway, no one’s filed a missing persons report for me, right? Can’t I just stay with you?”

“How do you know about me?” Lena asks, and Aislin frowns, frustrated again. Her forehead crinkles in a very familiar way, and Lena has to blink and shake her head against the feeling that she knows this girl. Knows her very well.

“Well, you’re…famous. And smart and beautiful, and I just thought…” She shrugs, looking lost and helpless. “I just wanted to grow up to be like you, and I didn’t... I…”

“Aislin, that’s very sweet, but I don’t have…the resources to be a parent. You should be with your family.”

“You don’t want me either,” she sighs, tears springing to her eyes. “It didn’t work.”

“What didn’t work?”

“I was going to surprise you. It was my secret project. And when… and then… I ended up too far back! And now the lab doesn’t even exist, and you don’t like me, and she’s still here, and I just…” 

Aislin puts her head down on her arms and cries in earnest. Lena tenderly smooths her hair. “Aislin, tell me what’s going on. Tell me everything, and I can help you.”

But the girl clams up and refuses to utter another word. Lena sighs and gets up. Without even thinking about it, she calls Kara, and before she can blink, Kara is in the doorway, holding a box of pastries. “Hi, can I talk to her for a minute?” Kara asks, setting down the box, and Lena nods. 

“I don’t want to talk to you,” Aislin says distrustfully, but she can’t help eagerly eying the pastry box. “What’s in there?”

“Cinnamon rolls, glazed donuts, and chocolate chip muffins.”

“How did you know?” Aislin demands. 

“Those are my favorites too,” Kara says gently. 

Aislin sighs and approaches the table where Kara sets out three of the treats on a plate for her. “I’m sorry,” Kara whispers, and Aislin shudders. 

“You were supposed to save her.”

“I know." It’s been a long night of theorizing and soul searching, but Kara has the answer. This girl is Lena’s daughter from the future. She’s here because Lena has died.“What’s your name?” Kara asks, so Aislin tells her. 

“How do you know why I’m here?”

“You look just like her. You sound just like her when she’s angry with me.”

“So you know I’m her daughter. Do you know I’m your daughter too?” Aislin asks slyly, and all of Kara’s calm acceptance of the situation crumbles.

“I—what?” The night before was supposed to have been their first date. Their very first. And now here’s—their daughter. “

Didn’t you wonder how I knew who you were? Why would I expect Kara Danvers to have saved her?” Aislin asks, now calmly chomping on a donut. 

“Because I—oh, shit.”

“She’s not going to believe you. She never believes your crazy stories.”

Kara huffs, trying to put some order to her thoughts. She finally figures the first order of business is keeping Aislin safe. “She’s going to want to get you back to your family. What did you tell her?”

“That my mom’s dead and my other mom and brother don’t need me. You always loved him better.”

“Your brother?” Kara asks, voice cracking, and Aislin nods, suddenly taking a savage glee in what this information is doing to Kara. 

“I could tell you your whole life,” she realizes, but Kara puts her hand up.

“Don’t. Not for me. For yourself. The more I know about the future, the more it changes. If you want to still be born, to still be Lena Luthor’s daughter, then you have to stop.”

“Why?”

“What if I decided to never see Lena again? Do you think she’d still have you? And your brother? She might have children with someone else, but they won’t be you or your brother.”

“Oh,” Aislin says, donut halfway to her mouth. “I should have… I’ve been…”

“I can get you home,” Kara offers. “To before she died. And you can tell me, okay? Tell me in time to save her.”

“You can?” Aislin asks, scrambling off her chair. 

“I think so. But we don’t have the right machine yet. You’re going to help me make it.”

“Okay!” Aislin says joyfully, and throws her arms around Kara’s neck. 

“We cannot tell Lena, though, okay? It could change your entire timeline.”

“Okay,” Aislin says solemnly. “I promise.”

\--

Lena knows Kara is good with people, but she is still stunned to return to the kitchen to find the once-hostile Aislin in her lap at the table. “Hi. We bonded over baked goods,” Kara says charmingly, and they both grin at her in a way that makes her almost lose her balance. 

How do they have the exact same smile?

“Can I borrow her for the day?” Kara asks winningly, and Lena frowns. 

“Shouldn’t we…be looking for her family?” she asks, trying to scold Kara with her eyes. 

“We are!” Kara says brightly, and Aislin nods happily.

“Is this…an alien thing?” Lena asks cautiously.

“Kind of?” Kara says.

“Don’t worry,” Aislin says. “I know what I’m doing, and Kara is going to help!”

And what can Lena say to that?

\--

Lena goes to work, trying not to overthink the Kara and Aislin situation, but really what else can she think about? A mystery girl in her office, Supergirl, and her romantic feelings for her best friend all wrapped up into one confusing bundle. 

Still, business is business, and she powers through her day, only pausing once to wonder how Kara and Aislin are doing.

\--

“You…built a time machine,” Winn keeps saying, as Aislin scrambles around for tools and spare parts. 

“Winn! Yes, she built a time machine,” Kara grouches. “We explained the basics to you.”

“Uncle Winn, you helped me,” Aislin says proudly. “We figured out how to power it without blowing the entire state’s power grid!”

“Did you blow the entire state’s power grid?” Kara asks, and Aislin smiles sheepishly. 

“Noooot quite?”

“Hmm. She just might be your daughter, Kara,” Winn laughs, and Kara grins. 

Now that Aislin has explained the mechanisms, Kara and Winn can work on fine-tuning it. Aislin obviously hadn’t meant to send herself twenty years back in time, but she hadn’t overshot in a disastrous way. Still, getting the machine to a precise date is going to be tricky.

“Ugh, god, do you know who we need for this?” Winn asks, flinging his date-setting device to the ground, frustrated.

“Lena,” they say together, and they both sigh.

Aislin has fallen asleep curled up on discarded ship parts, still clutching a wrench, and Kara and Winn are staring at a small device that should create a time distortion field. The device to set the date, however, is in shambles. 

“We really can’t tell her?” he asks, and Kara shakes her head.

“Well. We don’t have to figure the whole thing out today. I’ll take Aislin home for tonight, and we’ll get back to work in the morning.”

“Sure,” Winn says blearily.

Kara goes over and carefully scoops Aislin into her arms. She assumes she’ll just take her to her own apartment, but then she thinks about how Aislin is here for Lena.  
So she and the sleeping girl end up in Lena’s doorway at eleven o’clock that night. “Hi. Um… She’s really crazy about you? And even though we worked together today, she might be mad to wake up at my place,” Kara says sheepishly, and Lena silently lets them inside. 

“Who is she, Kara?” Lena asks as Kara settles the girl on the couch. 

“Someone...very important,” Kara says quietly. 

“She looks like me. Doesn’t she?” Lena asks, and Kara nods carefully.

What can she tell Lena?

“Don’t ask too many more questions,” she begs. “This is all…very precarious.”

Lena nods, seeming to understand, and tugs Kara into the kitchen. “We missed our date again,” she says, and Kara smiles bashfully. “I have leftover pizza?”

“How’d you know?” Kara says, and Lena kisses her softly. 

“I know you, Kara Danvers.”

Kara lets her forehead rest against Lena’s, and Lena gently smooths her hair. “God, why did it take me so long to get here?” she murmurs, and Lena kisses her again.

"There was never any rush, Kara.”

And for the first time since Aislin had appeared in Lena’s office, Kara’s heart quiets. Of course this is the woman she marries, has children with. 

Of course.

\--

They eat reheated pizza at the kitchen island, both constantly looking over at Aislin asleep on the couch. “Our daughter,” Kara keeps thinking, in awe.

When the pizza is gone, Kara cleans up the kitchen and lets Lena lead her to bed. They change into pajamas and wind around each other, Kara resting her forehead against Lena’s shoulder. “She’s the best of both of us. Isn’t she?” Lena says quietly, and Kara sighs an affirmative. 

But Lena has fallen asleep before she can ask any more questions, and so Kara just holds her and lets herself drift off to sleep. 

\--  
Morning finds Aislin in bed between them, head pillowed on Lena’s shoulder where Kara’s had been earlier. Kara is startled, but realizes to Aislin it must feel natural, comforting. She knows how much it hurts to lose a parent, how badly Aislin must have wanted to do this from the beginning. So she smooths her hair and kisses her cheek before getting up and leaving her safe with Lena. 

Lena wakes up with a small body attached to her back, and it is disconcerting to say the least. When she sits up, Aislin reaches out for her in her sleep, so she carefully pulls the girl into her lap. “I wanted you to be proud of me,” Aislin mumbles, not really awake yet. “I worked so hard.”

And Lena doesn’t know why or how this is happening, but it’s so easy to tell Aislin the only thing she, herself, has ever wanted to hear. “I am so proud of you,” she says softly, and Aislin cuddles against her with a sigh of satisfaction. 

She lets Aislin sleep in her lap for a while longer, absently smoothing her dark hair. If she is who Lena thinks she is… There is going to be a lot to talk to Kara about. 

Kara steals back into her bedroom while she’s watching Aislin sleep and kisses her head as she hands her a mug of coffee, and she feels a weird sense of déjà vu. Like she’s remembering the future. “Kara, tell me everything,” she demands suddenly, looking up at her. 

Aislin stirs and sits up, rubbing her eyes. “Oh,” she says, embarrassed, realizing she’s in Lena’s lap. “Sorry, I…”

“Don’t apologize, sweetheart,” Lena says gently, and Aislin’s eyes fill with tears, but she shakes her head. “She told me not to tell you who I am,” she says quietly. 

“She didn’t realize I’m much smarter than she is,” Lena teases, and Kara barks a laugh while Aislin smiles a watery smile. 

Kara sighs but then squares her shoulders. “Well. We’re all going to the DEO this morning, then.”

“If she knows, we should go to LCorp. That’s where I built it,” Aislin says eagerly, scrambling off the bed. 

“We’re going to stick to the DEO,” Kara insists. “It’s safer.”

“Is it?” Aislin asks, looking up at Lena.

“Probably,” Lena says. 

“Go wash up. There’s a toothbrush for you in the bathroom,” Kara says, scooting Aislin toward the door, and she scampers off to obey. 

“Tell me everything, Kara. The timeline’s already garbage if she’s here,” Lena says expectantly.

Kara sighs. “We haven’t even had our first date yet. And here we are, meeting our daughter.”

Lena’s known for almost twenty-four hours now, but hearing Kara say it out loud sends a jolt through her heart. Kara notices and blushes, then looks worried. “It’s all right. I know who she is.”

“You know she’s mine, not just yours?” Kara frets, and Lena nods.

“She’s so much like you she takes my breath away.”

Kara laughs a little and awkwardly clasps her hands behind her back. “That’s…how she makes me feel about you.”

Lena stands up and leans up to kiss Kara softly. “I have no idea what I could possibly do to deserve being the mother of your child, but… Well, I guess we’ll find out, won’t we?”

Kara blushes again and wraps Lena up in her arms. “I already know,” she murmurs, and their tender moment is immediately disturbed by their pre-teen daughter from the future. 

“I think I figured it out!” she hollers, waving her toothbrush in the air. “I just have to tell Uncle Winn. Come on, come on.”

“Aislin!” Kara laughs, gently tackling her. “Give us a minute to get dressed. And then eat breakfast.”

“Okay, but hurry,” Aislin says, running back to the bathroom. 

“Yup. She’s your daughter,” Lena laughs, and Kara grins. 

—

It isn’t until later, while Winn takes an over-energized Aislin out to pick up lunch that Lena thinks to ask why Aislin has come back to the past. She says it absently, like she doesn’t expect Kara to have an answer, but she doesn’t miss the way Kara goes rigid at her question. “You know why she’s here?” Lena asks, and Kara swallows hard. 

“You remember how much she didn’t like me at first?” Kara asks, looking everywhere but at Lena. 

“Yes,” Lena says slowly, as a theory begins to coalesce. “Something happened to me, in her time, didn’t it? Something she blamed you for?”

“You died,” Kara says quietly, and Lena feels as though she’s left her body. “And I couldn’t save you. All my powers and all my training, and I couldn’t save you.”

“Oh. Kara,” she says, stunned. “Have you… You knew… How…” Her mind reeling, she stumbles away from the bank of PCs where she and Winn have been working. 

Kara reaches out to catch her, but she squirms away. “I’m sorry. I really didn’t… I was hoping I could fix this without… I mean, I just didn’t want to cause you pain.”

“I need to… This… It was already too much, and now… I have to go,” she says abruptly, and Kara stands there, frozen. 

She’s still standing there, in the middle of the room, staring at the time device, when Aislin and Winn return. “Where’s Mo—Lena?” Aislin asks brightly, and Kara snaps back to herself. 

“Oh, some crisis at LCorp. She said she’ll be back as soon as she can,” Kara lies smoothly, and Aislin must be used to that, in her time, so she just nods and offers Kara a burrito.


End file.
